Flush pin gauge



H. G. CRAIG FLUSH PIN GAUGE Aug. s, 195o Filed June 20, 1945 ,A ra/7m, A25 Mawr Gf (kA/6,

l @ro/@NEX Patented Aug. 8, v:1950

UNITED Harry.-G.'VGraig,Evansville,1nd.assignorfofone# halfto Walter H.ySchnake,,Evansvilla-lnd. i z

"Applilation June zo, 1945; sensi Ntfooss Y. l "This invention relatesto pin gauge and has for a primary object apro-A vision in such a gaugeof a structure whereby the gauge may be used throughout -a Wide rangeofdimensions to be checked, indicating for each particular setting of thegauge the checked di-A mension within the required tolerance limits,whereby the dimension to be checked, 'such as-a depth of a hole,' may atonce be indicated by the gauge-both visually and by feel.

Heretofore such gauges for production work have been made forthe'particular dimension to be checked and are useless in checking otherdimensions varying therefrom.vv This meant that a large number of gaugeswould ordinarily have to beprovided, not only to 4check the varying holedepths, but with no provision for indicating the tolerance range.

' By use of my invention, the gaugemay'be initially setto checkthespecified dimension; and the gauge so used throughout the productionrun. Thereafter the gauge may be reset for a different dimension as maybe desired and 'again ybe used without alteration other than merelyresetting it, and when necessary, substituting a diieren't length ofpin. No change, howevenywould be made in the gauge itself.y v

These and many othery objects and advantages of the invention Awillbecome apparent tol those versed in thel art in the followingdescription of one particular form of the invention as illustrated inthe accompanying drawing, in which 'i V `Fig. 1 is a view in sideelevationof a structure embodying the invention; y `lig. 2, a view insection on the line 2--2 in Fig. 1; y

Fig. 3. a view in end elevation; f (Fig. 4; a view vin opposite endelevation;

Fig- 5, a View in section on the line 5-5 in Fig.1;and

Fig. 6, a view inA Section on the line [iQ-#6 in Fig. v2.

Like characters of reference indicate likeparts throughout the severalviews in the drawing. l y'.t 'form an anvil I6 cylindrical in v.shapeand preferablyV of considerable mass proportionately tovother parts ofthegauge as indicated inthe drawing. Centrally from this anvil I0extends integrally therefrom a tubularj ste'n' II. The anvil I 0i'sp'referably made of tool steel,`hard ened and finished ground overall vofithose external surfaces. The stem II is likewise groundthroughout itslength.

" sleeve I2 is formed to have acentral bore within which is slidinglyreceived with; a" 'close aJolaims. (crfs's-ifvmf a production 'ush ZIOfit thestem-'I I @The end portion of'the' sleev'e Il! which'approach'esthe anvil I0 is enlargedcy-` lindrically and is split'throughv on one side'by the slot I3, and then'a screw I4 is chordallypassed through this enlarged end across the slot I3 toscrew-threadedlyengagethe end whereby thatend may v'be pinchedl together around thestemvII as a means for fixing the sleeve 4I2 in any desired positionlongitudinally of the stem.l -1The opposite rend ofthe sleeve I2 isprovided witha `reduceddiameter portion I5, the external surface of`whichI is screw-threaded to receive thereoverthe internallyscrew-threaded portion o'f' the thimble I 6. lhis thimble I6 has askirtI'I `whichwilltelescope over'the'sleeve I2 i'n the nature ofi amicrometer caliper sleeve.` A bevf elledfend portion'IS''f the thimbleI6 is graduated; asindica'tedfin-Fig. f1,' andthe external surfaceoflthe sleeve I2over` which the skirt I1 extends is graduated by''parallellines I9 extending cir# cumferentially'around the sleeve.

"Thefsleeve I2 has va semicircular post 20 eX-L tending' on through"the` central bore :ofthe thimble I6 to extend normally therebeyond. Thispost-.26 ha'san outside radius of curvature such that the post'lhas l'aclearancebetween that surfaceandfthe"intrnal threads of the thimble I6.`The-post 20 has an inner radius of curvature Aa' few thousandths of aninch at least'le'ss than the'r'adius of curvature of the ends of thebore through the'stem I'I: -Thethimble I6 isprovided with an internal'an'-l nular groove 2I at the outer end-of the'threaded portion, Fig. 2jand' within this groove 2| is re'- ceived-th'e'Vsemicircular' foot 22ofv a slide 23. The slide 23 has an outer curved surfacev having a"radius of curvature corresponding to the ex'- ternalsurface 'of thepost'20, the slide and the postifrming when' placed one 'against theother, a y'continuous "cylindrical" surface therearound. Thislslide'23`has 'an' inner semicylindrical 'surfac,'ithe radius'ofcurvature of which equals that of-theiinner surface of the post 20.Thus, when the slide23 is vplaced against the postl 20, the contracting'surfaces of these'two members therebetween'beingdiametricauy mamar, a.cylindrical bore is left therethrough of continuousA diameter eventhoughthe slide 23 is shifted longitudinany'if 'the merece-of the post 2u.since the foot 22"of theslide23 is c'arried'vvithin the groove ZI of thethimble I6,` rotation of the thimble I6 will advance the slide 23 alongthe post 20 without rotative movement ofthe slide 23 by reason `oftheabutm'e'nt of the' slide23'by its flat face againstfthelatface'of'the'fpos't 2|.'I.'-`

The gauge pin 24 is carried to extend through the bore of the stem Iland project beyond the anvil I0. The pin 24 is longitudinally shiftablein respect to the anvil I within predetermined limits as determined bythe length of a at spot 25 formed along one side near one end of the pin24 within the post 20. A set screw 26 is screw-threadedly carried bythel post 20 to enter transversely thereof to have an inner end comewithin the ends f the 'flat spot 25 as a means of retaining the pin 24as above indicated. The pin 24 has a close sliding fit through a portionatleast of the anvil I0 and through the bore between the post and theslide 23.

Adjustment of the slide 23 toward the pest--2ll` is had by the expedientof providing a plurality of radical slots 21 across a reduced outerdiam;-` eter portion of the thimble I6 and then passing a nut 28screw-threadedly over thatportlon by means of a slightly tapered threadwhereby that. en d portion may be slightly contracted to secure thedesired lit relatively between the slide, post, and an internal wal-lofthe thimble i6 which fits. around the outside of the post .2li and theslide 23.

All of the parts are precision made` and interitted. The ends of the pin24 are ground square in relation to its axis and the .overall lengthofthe pin is ground to an accurate dimension.

Now by properly adjusting the anvil I!) in relation to the end of thesleeve l2 and by selection of the proper length nin r2.4, the thimblemay be revolved. to that setting. as indicated by the calibrations on`the end 0f the thimble and on the sleeve to carry the slide ,23accordingly longitudinally inwardly or outwardly inv respect to theouter end of the post 20 to set lthe, end vof thev slide 23 in thatVposition whereby the longig tudinal distance between the ends ofthe post2l! and the slide 23 will be the maximum tolerance permitted for theparticular dimension to bec-hecked. That is, ifA the end of the post 20is set in relation to. the outer face of theanvil l0 for. the minimumlimit of tolerance, the end of the slide 23 will beset for the maximumtolerance so' that when the gauge is placed over a hole '29. forexample, Fig. 1 and the pin 24 relS. on the bottom thereof, the upperend of the pin should lie between the ends of the post 2,!) and theslide 23 as indicated in Fig. 2, ifthat hole has been given a depth tobe within the tolerance limits forv which the gauge is set. Thisindication is visible by observing the position of the end of the pin 24in relation to the ends of the slide 23 and the post 20. That settingcanalso be determined very quickly by feel. 'Of course, if the end ofthe pin 24 is above the end o f the post 20 or below theend of the slide23, the hole is either not deep enough or is too deep accordingly. Thegauge mayy be very quickly set by loosening the screw I4 andshiftinguthe anvil l0 relative to the sleeve I2 to the desired distanceas may be checked by a micrometer caliper between'the end of its movablespindle and its anvil to have the end of the post 2U and the outer faceof the anvil l0 of the vgauge in vabutment therebetween. Inthe absenceof a Sufciently large caliper, a gauge block may be employed betweenthe. end of the. sleeve l2 and ythe opposing face of the anvil lll sincethose faces are ground to be parallel one with the other and the anvill0 is given a denite height.

While I have herein shown and described my invention in the oneparticular form, it is obvious that structural variationsy may beemployed without departing from the spirit of the inventionl and Itherefore do not desire to be limited to that precise form beyond thelimitations as may be imposed by the following claims.

I claim:

1. In a production flush pin gauge for gauging the depth of a hole, ananvil; a tubular stem extending from the anvil; said anvil and stem,li'aV-.irflg' bore" extending'axially therethrough; a `Vsleeveslidinglytelescoping over said stem; an outer end on said sleeve; saidsleeve being externally threaded at least toward its outer end; Ineensfor adjustably xing the sleeve at selected positions along the stem; apost extending longitudinally from-said stern in fixed relation thereto;a slide ufitting against and shiftable along l saidpo'st', athimbletelescoping over said post,

said slide, and said sleeve, and threaded internally. to engage with athreaded portion of the sleeve to have an outer end portion of both thesleeve .and the post to extendv outwardly bevond the thimble; meansinterengaging said slide with said thixnble to advance and retract the.slide along said post upon corresponding travel ci the thirnble; saidslide havingr an outer planar end Shiftable into and out of theme11@ 0fthe outer end of said post by said thimble travel; and a pin slidalblycarried in said bore to be shiitable .axially there@ am@ 31.09 .Sad1205.1? and haVllS il length exceeding the combined axial lengths oisaid anvil, stern and post;y whereby, upon seleclien @fille Properlength O f Pin .for the. depth, af the r0.1@ tot@ gallese, @smelling ofthe sleeve along the, Stem, and' the, turning 0f ille @liable i9! adjustthe. slide @ed a Permitted tolerance lllS tance'fromsaid post end, theouter end of. said iilfwl lie between 'the Slide elfld and the wel, endwhen inserted"intothe hole from the anvil endV of thegauge ywhen thathole depth is within the, predetermined tolerance range. 2 2.Ina"production hush pin gauge for gauging' depthof a hole, an anvil; atubular stem extending'from'the anvil;y said anvil and sternvv having aboreV extending axially therethrough; a. s jleeverslidin'gly telescopingover said stern; ,outerv end on said sleeve; saidsleeve being externallythreadedat least` toward its outer end; means ioradjustablyflxing thesleeve at selected gestions alenalll Stem: a post extendinglongitudinally from said stem in fixed relation therete: aSlideflttirle. against and Shlflable along Said post; a thimbletelescoping over said post, said slide, and said sleeve, and threadedinternally to engage with a threaded portion of the sleeve to have an@aber end. Portion @l both the Sleeve and the post to extend outwardlybeyond the thimble; means interengaging said slide with said thimble l0advance .and reifer-7i the Slide .alena Sala-Pest upon correspondingtravel o the. thimble; said slide" having an outer planar end shiftableinto and out of theplane of the outer end of Said post by said thimbletravel; and a pin slidably carried in said bore to be shiftable axiallythereof and along lsaid post and having a length exceeding @les@ambi-.nee 'axial lengths 0f Said anvil.; .Stem se@ posi; whereby. uponSelection. 0f the Proper. length of pin for the depth of the hole tpfbegauge. 'positioning 0f the Sleeve along the .stemt and the. turning @.fthe thimble lo adjust. .the Slide end permittedtolerance distance fromsaid post end, the outer end of said pin will be between the slide endand the post end when inserted into the hole from the anvil end oi thegauger when the@ bele- ,fleplh ls within. the predetermined i01- eraaerenee: .Salti 1205i.. beleg @1lv away delle being externally threaded atleast toward its outer end; means for adjustably fixing the sleeve atselected positions along the stern; a post extending longitudinally fromsaid stern in fixed relation thereto; a slide tting against andshiftable along said post; a thirnble telescoping over said post, saidslide, and said sleeve, andI threaded internally to engage iwith athreaded portion of the sleeve to have an outer end portion of both thesleeve and the post to extend outwardly beyond the thimble; meansinterengaging said slide with said thimble to advance and retract theslide along said post upon corresponding travel of the thimble; saidslide having an outer planar end shiftable into and out of the plane ofthe outer end of said post by said thimble travel; and a pin slidablycarried in said bore to be shiftable axially thereof and along said postand having a length exceeding the combined axial lengths of said anvil,stem and post; whereby, upon selection of the proper length of pin forthe depth of the hole to be gauged, positioning of the sleeve along thestem, and the turning of the thimble to adjust the slide end a permittedtolerance distance from'saidpost end, the outer end of said pin will bebetween the slide end and the post end when inserted into the hole fromthe anvil end of the gauge when that hole depth is within thepredetermined tolerance range; said post being cut away along one sideto form a surface over which said slide may travel, said post and saidslide together completing walls defining a bore therebetween and axiallyaligned with said stem and anvil bore; said thimble and said slideinterengaging means comprising a foot on said slide slidingly receivedin an internal annular slot of the thimn ble; outer surfaces on saidslide and said post forming a cylinder about which said thmble slidinglyturns rto maintain the slide against said post.

HARRY G. CRAIG.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 664,211 Clapp Dec. 18, 19001,317,746 Whatley Oct. '7, 1919 OTHER REFERENCES Machinery (magazine),page911, July, 1926.

